Well anyone can sue another person for anything. If he does sue you then you will have to defend yourself, however it's very easy to threaten to sue - seems to be a natural thing for people to say when they feel they've been wronged. It's another thing to actually go ahead and do it.
Unless you provided any type of explicit warranty, then the sale was as-is and the buyer has no recourse. It was up to him to inspect the vehicle prior to purchase.
The OP has been making the rounds of various legal site asking this question. Not sure if he'll return here but down the street he did say he printed the photo from a county public-access website from which one is able to obtain inmate information.
New York City is the only municipality in New York State that has the authority to promulgate it's own traffic laws, which are contained in the New York City Traffic Rules. All city parking violations are right in there. The VTL parking statutes do not apply in the city.
Yellow curbs mean nothing in NYC. You need to provide the charge as stated on the parking Notice of Violation. If you can't read it you should be able to pull up the NoV online.
Judge: those restrictions you cited do not apply in New York City
So then it would be a simple matter for you to use your tremendous wealth to retain your own counsel who is not a family member or working for your family law firm.